From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59CD4C2D0DB for ; Fri, 31 Jan 2020 13:31:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D9CC20CC7 for ; Fri, 31 Jan 2020 13:31:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580477501; bh=rGI+UF/ICJd+DA8hslNtVh1f+xovDraNDpFwivdJgEQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=UYNPuDlf5cuhBQU2R35FkXydBfpBTw/rpj/cyqTQDF+sZeBpvLVULIM7xh7wEIXjs 3Qw9ET2xnRpS3Ac7gX39ogKxLP7beZ0c+aMJ8VwcFZBRt31tDnZ2yUR6A0HwDtFqAG qo8Ugu/fhiVVBWsDsqZ4adPG5wnx3wdcnbCDMt8g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728620AbgAaNbk (ORCPT ); Fri, 31 Jan 2020 08:31:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:33814 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728514AbgAaNbk (ORCPT ); Fri, 31 Jan 2020 08:31:40 -0500 Received: from mail-lf1-f41.google.com (mail-lf1-f41.google.com [209.85.167.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4106320CC7; Fri, 31 Jan 2020 13:31:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580477499; bh=rGI+UF/ICJd+DA8hslNtVh1f+xovDraNDpFwivdJgEQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=lNh1WjFIpIEW9gXqIRSmZJAOjv3O4mh6mGQrDhX5I681cYGAB8HU+xBjBD2rJ1C9Q TJXUu70xcUSirXIZgn61heC1YOyaIndk86NtztEiWfuW+VPE4WHR42hV+ivyvdWash 4JYm9F+/bLF3lWQwcU2T8HrzxncujDFoDpSqLTdg= Received: by mail-lf1-f41.google.com with SMTP id v201so4846532lfa.11; Fri, 31 Jan 2020 05:31:39 -0800 (PST) X-Gm-Message-State: APjAAAUfOqiAnmYfk/Ca11X4t/qjG+9TuFvOGw62bnkuc8ANS+PDekVW 8KYpEZlp/CjWuHiHM5SE3J8Z8Z7xMR3a/4EKmoY= X-Google-Smtp-Source: APXvYqwSbqju6JUksaPdkz/97mfFYOYXw/rc+uN4pEE26ZZoKFaM+ty1mhlgkTYOmglIESjcDg0P8El//QIqqmY+O8o= X-Received: by 2002:ac2:4472:: with SMTP id y18mr5340968lfl.39.1580477497394; Fri, 31 Jan 2020 05:31:37 -0800 (PST) MIME-Version: 1.0 References: <20200127215453.15144-1-lukasz.luba@arm.com> <20200127215453.15144-4-lukasz.luba@arm.com> In-Reply-To: From: Krzysztof Kozlowski Date: Fri, 31 Jan 2020 14:31:26 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 3/3] ARM: exynos_defconfig: Enable Energy Model framework To: Bartlomiej Zolnierkiewicz Cc: lukasz.luba@arm.com, kgene@kernel.org, linux-arm-kernel@lists.infradead.org, "linux-samsung-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , devicetree@vger.kernel.org, linux-pm@vger.kernel.org, myungjoo.ham@samsung.com, kyungmin.park@samsung.com, Chanwoo Choi , robh+dt@kernel.org, mark.rutland@arm.com, dietmar.eggemann@arm.com Content-Type: text/plain; charset="UTF-8" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, 31 Jan 2020 at 14:30, Bartlomiej Zolnierkiewicz wrote: > > > Hi, > > On 1/27/20 10:54 PM, lukasz.luba@arm.com wrote: > > From: Lukasz Luba > > > > Enable the Energy Model (EM) brings possibility to use Energy Aware > > Scheduler (EAS). This compiles the EM but does not enable to run EAS in > > default. The EAS only works with SchedUtil - a CPUFreq governor which > > handles direct requests from the scheduler for the frequency change. Thus, > > to make EAS working in default, the SchedUtil governor should be > > configured as default CPUFreq governor. Although, the EAS might be enabled > > in runtime, when the EM is present for CPUs, the SchedUtil is compiled and > > then set as CPUFreq governor, i.e.: > > > > echo schedutil > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor > > echo schedutil > /sys/devices/system/cpu/cpu4/cpufreq/scaling_governor > > > > To check if EAS is ready to work, the read output from the command below > > should show '1': > > cat /proc/sys/kernel/sched_energy_aware > > > > To disable EAS in runtime simply 'echo 0' to the file above. > > > > Some test results, which stress the scheduler on Odroid-XU3: > > hackbench -l 500 -s 4096 > > With mainline code and with this patch set. > > > > The tests have been made with and without CONFIG_PROVE_LOCKING (PL) > > (which is set to =y in default exynos_defconfig) > > > > | this patch set | mainline > > |-----------------------------------------------|--------------- > > | performance | SchedUtil | SchedUtil | performance > > | governor | governor | governor | governor > > | | w/o EAS | w/ EAS | > > ----------------|---------------|---------------|---------------|--------------- > > hackbench w/ PL | 12.7s | 11.7s | 12.0s | 13.0s - 12.2s > > hackbench w/o PL| 9.2s | 8.1s | 8.2s | 9.2s - 8.4s > > Would you happen to have measurements of how much power is > saved by running hackbench using "SchedUtil governor w/ EAS" > instead of "SchedUtil governor w/o EAS"? That's a good point and quite important reason behind enabling (or not) EAS... Best regards, Krzysztof